Integrated solar heating unit

Abstract

The instant solar heating unit takes advantage of anti-reverse-siphon techniques developed by the inventor and combines anti-freeze features, and houses the entire unit in a wedge-shaped, integral cocoon to retain heat and enclose the piping and fixtures. In the preferred embodiment, the collector panel has tube manifolds which are adjacent the hot water tank to keep them from freezing, and the tubes of the collector, which are exposed through the panel glazing to radiate their heat at night, are expansible to prevent their rupture in the event of a freeze.

I claim: 
     
       1. An integral solar heating unit with an integral solar collector and hot water storage system, said unit comprising: (a) a housing;   (b) a flat plate solar collector panel mounted in said housing and having a generally horizontal upper edge and an uninsulated, open back surface;   (c) a cylindrical hot water tank operatively connected to said solar collector panel and mounted in said housing generally parallel to and adjacent to said upper edge;   (d) said housing comprising a hood around said tank a pair of side skirts extending down at the sides of said panel, said hood and side skirts terminating at lower edges which together substantially define a plane such that upon placing said heating unit on a generally planar surface, said housing substantially encapsulates said collector panel and hot water tank in a substantially enclosed air space;   (e) said collector including a plurality of longitudinally extended U-shaped collector tubes and a glazed window to pass radiation through to said collector tubes, and a first cold water manifold connected to said tubes for delivering fresh water thereto and a second hot water manifold connected to said tubes to remove heated water therefrom, and said manifolds are adjacent and at least somewhat above and in direct thermal contact with said tank; and,   (f) said skirts and hood lapping around said collector panel, exposing only said glazed window, such that everything else in said heating unit is enclosed by said housing such that heat emanating from the uninsulated, open back face of the collector and tank is captured and retained by said housing to warm said manifolds.   
     
     
       2. Structure according to claim 1 wherein at least those portions of said tubes exposed through said glazed window are internally expandible, by virtue of being lined with a compressible lining material, which is sufficiently compressible to permit the expansion of freezing water therein without causing damage to the tubes. 
     
     
       3. Structure according to claim 2 wherein the above-mentioned exposed portions of said tubes are internally lined with EPDM to accomodate the expansion of water therein. 
     
     
       4. Structure according to claim 1 wherein all the piping, by which said hot water tank is operatively connected to said collector panel, which is external of said tank and collector panel, is enclosed within said housing and thus warmed to protect against freezing. 
     
     
       5. Structure according to claim 4 wherein said piping has a cold water inlet to supply said collector panel with fresh water, and including a dip tube communicating with said cold water inlet and extending down into the lower portion of said hot water tank to define the depending portion of an anti-reverse-siphon loop. 
     
     
       6. Structure according to claim 5 and including a valved bypass connecting said cold water inlet directly to said tank to bypass said dip tube to permit said heating unit to reverse siphon in a natural way when said valve is actuated to prevent said collector panel from freezing. 
     
     
       7. Structure according to claim 6 and including an immersion heater in said tank to further warm said collector panel and accellerate the reverse flow therein to assist in preventing same from freezing when the bypass valve is actuated.